diff --git a/addons/portal/wizard/portal_wizard.py b/addons/portal/wizard/portal_wizard.py
index df3ff61f4f3..ecbec057c75 100644
--- a/addons/portal/wizard/portal_wizard.py
+++ b/addons/portal/wizard/portal_wizard.py
@@ -117,7 +117,9 @@ class wizard_user(osv.osv_memory):
 
     _columns = {
         'wizard_id': fields.many2one('portal.wizard', string='Wizard', required=True, ondelete='cascade'),
-        'partner_id': fields.many2one('res.partner', string='Contact', required=True, readonly=True),
+        'partner_id': fields.many2one(
+            'res.partner', string='Contact', required=True, readonly=True,
+            ondelete='cascade'),
         'email': fields.char(string='Email', size=240),
         'in_portal': fields.boolean('In Portal'),
     }